After the fall of Northeast China, the Japanese attempted to turn North China into a second "Manchukuo" and committed a series of murders in Beijing, causing panic among the people. The 9th Army sent troops into the city to form a military police regiment, with Qiu Sanqi as the head. Qiu Sanqi was a famous dandy. Therefore, the Japanese and Chiang Kai-shek gave him the important task of "anti-communism" and ordered him to solve the mystery. However, they did not know that Qiu Sanqi was a Communist. He had to deal with it carefully, to protect himself while smashing the enemy's conspiracy. After the "Lugouqiao Incident", Qiu Sanqi served as the head of the student corps composed of anti-Japanese students, led the student corps to fight bravely, and composed a heroic hymn.